Merge pull request #88 from freude/develop

updated coveralls token

.travis.yml

@@ -5,7 +5,7 @@ python:
 install:
     - sudo apt-get install libopenmpi-dev
     - pip install python-coveralls
-    - pip install coverage
+    - pip install coverage==3.7.1
     - pip install -r requirements.txt
     - pip install .
 # command to run tests